Battery still being drained.
 

I know this is becoming old very fast. So far I know the altenator is good, the regulator is good and the battery is good. I know the horn is good as well. I have removed all fuses one at a time and the draw on the battery did not go away.

When I removed the 4 connector bar from my external regulator the draw on the battery went out. I assumed the regulator was bad. I hooked the regulator back up, the light came back on and then I went over and disconnected the main wiring harness from the firewall where it plugs into the back of the fuse box? The light went out again, so this leads me to believe the draw comes from inside the truck?

I know the draw is from inside the truck and must not go through the fuse box, since I removed all the fuses, one at a time and the light never went out. I believe the faulty component is somehow tied to the brown wire that runs to the regulator, since the other 3 wires on it run to the altenator and I have already checked them.

Can anyone tell me how or where the brown wire runs? A second part of the problem, is my uncle tells me from the looks of it, my ammeter wasnt working correctly in the first place. Could something be wrong with the ammeter itself and be causing the draw?

Anymore advice would be much appreciated.

one time i had a draw on the battery and i couldnt figure it out, what it ended up being was the alternator. it charged the system while it was running but had a drain when it was off. do the little light trick and unplug the alternator plug.

The ammeter cannot cause a draw the way it is wired in from the factory. The brown wire is the exiter wire from the ignition and should only have voltage with the ignition switch on.

Jim

Thanks for the tip. Someone else suggested this in one of my many other posts and it was good. I have tested the altenator by taking the battery leads off while it was running and also done the light trick and removed all 3 wires connected to the altenator and the light stayed on. So I am calling the altenator good? Thanks! Also the light did go out when I removed the main wiring harness from the firewall where it plugs in, thats what leads me to believe its inside.

Hey sooner,sorry to keep bugging you but I see you are on the right track and have traced the drain to the interior of the cab. I found this little tidbit on the web and it relates to the ammeter.
VV
http://www.misterfixit.com/dedbatt.htm
The brown wire is the feed wire for the idiot light and is paralled with the key switch so when the key is turned on the light comes on to charge the sensing circuit in the alternator. Un plug the connector on the key switch and see if the test light goes out.Maybe the key switch is shorted internally. There is a wiring diagrahm in the FAQs on your truck and I'll see if I can find the thread. Hold on.
VetteVet

So this means I should focus on my ignition switch? Whatever I focus on shouldnt be routed through the fuse box, because I did check them all by removing them one at a time.

wiring diagram
 

here is the link for the wiring diagram. I find it a little hard to read but then my eyes aren't what they used to be. Thttp://www.geocities.com/chevroletc1070/instrum2.html he key switch is at the top of the page. Good luck.

VV

I have had this happen a few times over the years, This is a sign that the Diode has went bad...and is a easy fix.

Thanks for the link VV. Ill try to make heads or tails out of it.

New developement! I decided to jump across the connectors from the main wiring harness to the back terminal of the fuse box, located on the firewall. Well its not the brown wire at all. The jumper that caused the draw light on the battery to come on and off when connected or disconnected was the fat red wire. If I am not mistaken, when I was inside the dash before, the fat red one is the constent 12v power, like the one to the key cylinder and cig lighter? I tried removing hte connector from the back of the key cylinder but it wouldnt budge. Here is a pic of the wire that is causing the draw on the battery.

drain
 

You are getting closer. The main wire is the power wire from the battery to the ignition and cigarette lighter as you said. the problem is that it is feeding back to the ground through some draw like a dome light or radio power that is on all the time and may not be fused. Since you unplugged the regulator and the light went out then I think like Jimk said that"you're feeding the alternator through that. Also like Jimk said the diode can be bad in the alternator and cause the same drain. It is possible that the large red wire is draining back through the alternator if the main diode is bad. Did you not say in a previous thread that you had unplugged all the alternator wires and the light stayed on. That is what pointed me to the brown wire to the key switch.
Here is a link to the key switch harness that shows the plug and tells how to remove it.http://67-72chevytrucks.com/vboard/s....php3?t=123712
Vettevet

Does your horn work? If it does then disregard. If it is unplugged from the horn, plug it in to see if will make you hit your head on the hood. If you hit your head then it may be the horn relay or be a stuck/bad horn button.

VetteVet, what did you do in the AF?

Just my two cents: The memory from a stereo will draw enough to light a testlight, I would also unplug the headlight switch as it does not go through the fuse box. The brake light switch may also be hanging up, again this would not show up when pulling fuses. Not an expert just tryin to think outside the box.

Good luck

Vettevet in the AF
 

Hi sonny thanks for asking. 4 years active duty in SC on c-130 C-141
22 yrs Michigan Air National Guard ( crew chief on A-37s and A- 10s ).
Lotsa war stories. :)

VetteVet

I recommend what sonny said about the horn relay circuit possibly being the problem.

VetteVet,

Working on 20 as active duty. Today I celebrated passover. The results came out today and I didn't make SMSgt (1st time testing). I am a C-130 crewchief. Flyin' a desk training young snot nosed kids how to do battle damage repair. I flew on special ops C-130s as a flying crewchief.

Sooner 1970 K10,
If you have a voltmeter that can read amperage--then instead of using a lightbulb, use the meter in series to figure out how many amps the circuit is drawing. Low amps is probably something electrical (alternator, regulator, switch, etc.) high amps or blows the meter's fuse (prob 10 amp) then start looking for a short somewhere.

I was just skimming the schematic and I was think that it could be an outside chance that it may be your ignition switch. The only other way I can see the brown wire getting juice from other than the alternator is the ignition switch. If the ignition switch is not the culprit, I would look for something recently added electrically that may be the culprit where someone may have mistaken the wrong wire to tap into. I had recent bout with wiring when I had the white wire from the starter get up against the header and kill my power to the distributor. That sucked , because you could only see the wire from underneath.

Sonny

Take your fuse panel down and look behind it . Will probably find a fried wire.

Yes Yes Yes.... I am having that problem... what is the fix?? (in suspense)

Replace voltage regulator if externally regulated or replace/rebuild alternator if internally regulated.

Sonny